AC RMS Calculator
Enter a peak (or RMS) AC value to instantly convert between peak, RMS, and peak-to-peak voltage or current.
Input
Quick Presets
Results
Enter a value and click Calculate.
RMS Voltage
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Peak Voltage
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Peak-to-Peak Voltage
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Formulas Used
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Summary
Enter a peak (or RMS) AC value to instantly convert between peak, RMS, and peak-to-peak voltage or current.
How it works
- Select whether you are entering a Voltage or Current value.
- Choose the input type: Peak or RMS.
- Type your value in the input field.
- The calculator applies Vrms = Vpeak / √2 (or rearranges for the reverse).
- Results for RMS, Peak, and Peak-to-Peak are shown instantly.
Use cases
- Convert mains supply voltage (e.g. 120 V or 230 V RMS) to its peak value.
- Find the RMS current through a resistor driven by a peak AC source.
- Verify oscilloscope peak readings against datasheet RMS ratings.
- Design power electronics where both peak and RMS values are required.
- Check transformer winding voltages during AC circuit analysis.
- Understand the relationship between peak and effective (RMS) power delivery.
Frequently Asked Questions
Last updated: 2026-06-11 ·
Reviewed by Nham Vu